TOKYO -- A Japanese utility agreed yesterday to shutter three nuclear reactors at a coastal power plant while it builds a seawall and improves other tsunami defenses there.
Chubu Electric Power Co. acted at a special board meeting after Prime Minister Naoto Kan requested the temporary shutdown at the Hamaoka plant amid concerns an earthquake magnitude-8.0 or higher could strike the central Japanese region sometime within 30 years.
The government's decision came after evaluating Japan's 54 reactors for quake and tsunami vulnerability after the March 11 disasters that crippled the Fukushima Dai-ichi plant in northeast Japan. The Hamaoka facility sits above a major fault line and has long been considered Japan's riskiest nuclear power plant.
Chubu Electric president Akihisa Mizuno described Kan's request, which was announced on live television Friday evening, as carrying immense weight. His company's response reflects its commitment to putting safety first, Mizuno said.
The utility will shutter the No. 4 and No. 5 reactors at the plant, Mizuno said. It will also indefinitely delay a planned resumption of the No. 3 reactor, which has been shut down for regular maintenance since late last year.
The plant's nonoperating No. 1 and No. 2 reactors were slated for decommission before the disaster.
About 79,800 people live within a 6-mile radius of the Hamaoka plant, about 125 miles west of Tokyo.
Nuclear energy provides more than one-third of Japan's electricity, and shutting the Hamaoka plant is likely to exacerbate power shortages expected this summer. The three reactors account for more than 10 percent of Chubu's power supply.
The Hamaoka plant provides power to central Japan, including nearby Aichi, home of Toyota Motor Corp. The potential electricity problems only add to the automaker's woes.
Like other Japanese automakers, Toyota was hit hard in its production capacity when the earthquake and tsunami devastated the country's northeast coast. The region is home to a network of key auto-parts suppliers whose plants were crippled by the natural disasters and subsequent electricity shortages.